CVE-2026-91939 (GCVE-0-2026-91939)

Vulnerability from cvelistv5 – Published: 2026-09-15 20:56 – Updated: 2026-09-24 14:22
VLAI
Title
Cotonti 1.0.0 Comments Plugin PHP Object Injection via ci Parameter
Summary
Cotonti 1.0.0 Comments plugin passes the ci GET parameter to unserialize() without allowed_classes restriction, allowing unauthenticated attackers to instantiate arbitrary PHP classes with attacker-controlled properties. Attackers can exploit PHP object injection through crafted serialized payloads to trigger gadget chains and achieve database manipulation or code execution.
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-16 19:17 UTC
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6373 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Cotonti Cotonti Affected: 1.0.0 , ≤ 1.0.0 (custom)
    cpe:2.3:a:cotonti:cotonti_siena:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-13 00:00
Credits
Harsh Raj Singhania
Show details on NVD website
To clipboard 

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